Modern automotive vehicles, mass produced for the consumer market, have been the recipient of a surge in application of computer arts to the control systems. Most of the activity which began in the 1970's and has accelerated in the 1980's, has involved the application of small digital or analog computers to monitor and control the operating parameters of the automotive engine and its components. Most of the applications involve the connections of a computer "box" to a wiring harness which collects wires leading to and from sensing elements and control elements. A multiplicity of such wires are collected at a wiring harness which has a set of male connector pins which are removably plugged into a female connector plug on an electronic control assembly. Alternately the wiring harness may have the female connecting plug and the electronic control assembly a plurality of male connecting pins insertable therein. In this way, each wire leading from a sensor or control element becomes a circuit which is easily connected and disconnected to the proper lead of the electronic control assembly computer. The circuits completed through the wiring harness and electronic control assembly and the voltages and resistances of the various control and sensing elements are pre-selected at the factory to produce average performance of the engine.
In order to produce enhanced performance of the engine it has been found desirable to add certain circuit altering devices in some of the sensing and control circuits, but there has been no easy inexpensive way to accomplish this. One possible way would be to replace the electronic control assembly with one containing different values for certain circuit elements or operating at different voltages, but this is expensive and impractical. Another solution would be to break an individual wire leading to the wiring harness to add certain resistors, capacitors, transistors, and/or diodes, or to replace the sensing or control elements with ones having different values for operation. This approach would be equally expensive and difficult and could not be done quickly and easily. Moreover, such changes would be permanent and not easily reversed if it was desired to put the control system back to its factory settings.
The present invention provides an inexpensive, compact interactive interconnecting unit insertable between the wiring harness and the electronic control assembly to instantly and simultaneously enhance the performance characteristics of the engine by adding circuit altering devices. The modular unit can be quickly and easily removed to return the control functions to their original factory settings.